import java.io.*;
import java.net.*;
import java.util.Scanner;

import static java.lang.Integer.*;
import java.io.*;
import java.net.*;
import java.applet.Applet;
import java.security.MessageDigest;

/**
 * Created by zyl on 17-6-1.
 */
public class Server {
    public static void main(String args[]) {
        MyDC receiver = new MyDC();

        try {
            ServerSocket server = null;
            try {
                server = new ServerSocket(3500);
                //创建一个ServerSocket在端口3500监听客户请求

            } catch (Exception e) {
                System.out.println("can not listen to:" + e);
                //出错，打印出错信息

            }
            Socket socket = null;
            try {
                socket = server.accept();
                //使用accept()阻塞等待客户请求，有客户

                //请求到来则产生一个Socket对象，并继续执行

            } catch (Exception e) {
                System.out.println("Error." + e);
                //出错，打印出错信息

            }

            String line;

            BufferedReader is = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            //由Socket对象得到输入流，并构造相应的BufferedReader对象

            PrintWriter os = new PrintWriter(socket.getOutputStream());
            //由Socket对象得到输出流，并构造PrintWriter对象

            BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));
            //由系统标准输入设备构造BufferedReader对象


            //使用Hash函数检测明文完整性

            String x = sin.readLine();

            MessageDigest m2 = MessageDigest.getInstance("MD5");
            //使用MD5算法返回实现指定摘要算法的 MessageDigest对象

            m2.update(x.getBytes());
            byte a[] = m2.digest();
            String result = "";
            for (int i = 0; i < a.length; i++) {
                result += Integer.toHexString((0x000000ff & a[i]) | 0xffffff00).substring(6);
            }
            System.out.println(result);

            String match = is.readLine();
            if (match.equals(result)) {
                System.out.println("匹配成功");
            }

            System.out.println("Client:" + is.readLine());
            //在标准输出上打印从客户端读入的字符串


            line = sin.readLine();
            //从标准输入读入一字符串


            while (!line.equals("bye")) {
                //如果该字符串为 "bye"，则停止循环


                os.println(receiver.evaluate(line));
                //向客户端输出该字符串

                os.flush();
                //刷新输出流，使Client马上收到该字符串


                System.out.println("Server:" + receiver.evaluate(line));
                //在系统标准输出上打印读入的字符串


                System.out.println("Client:" + is.readLine());
                //从Client读入一字符串，并打印到标准输出上

                line = sin.readLine();


                //从系统标准输入读入一字符串

            }  //继续循环

            os.close(); //关闭Socket输出流

            is.close(); //关闭Socket输入流

            socket.close(); //关闭Socket

            server.close(); //关闭ServerSocket

        } catch (Exception e) {
            System.out.println("Error:" + e);
//出错，打印出错信息

        }
    }

}
